class Ticker {
    private _timer: number = 0;
    private _interval: number = 1;
    private _ratio: number = 1;

    // ... 其他代码

    update(deltaTime: number) {
        this._timer += deltaTime * this._ratio;
        
        if (this._timer >= this._interval) {
            this._timer = 0;
            // TODO: 执行某些操作
        }
    }
}